Fire-resisting cabinet



106-15Fp' v 46' Application July 3, 1944, serial No. 543,402

Pu.. n.041? ff f-glj-uNlTED STATES* PATENT .QFFlCE 4olaimsfcrios-s4) f fj This invention relates to improvements in lireresisting les, cabinets,safes or like containers,

metal casing lined with a suitable heat insulating material. A commonform of insulating material iis made of;g y psumor similar plaster-likematerial, molded in one piece within the outer casing to form an innerliner therefor. It has been observed that when the structures ofthe kinddescribed above are cailed upon to perform their ultimate function ofresisting fire and heat, certain gases are formed within the outercasing particularly when the master-liner gives upitspygatermgufmgrystalliaation in the form of steam underexcessive"lt.`"mth'ougldeh` -drolyzation of the lining material isusually relied upon as one of the factors contributing to the protectionof the contents of the container, yet theresulting steam pressuregenerated in the casing tends to separate the outer metal shell from itsliner so as to form a hollow space therebetween.

In carrying out my invention I provide an immy invention illustrated inthe drawing, the in vention is shown as applied to a typical form offire-resisting container suitable foruse as a file, cabinet, safe, orthe like, indicated generally at IG. The side, top and bottom walls Il,I2 and I3 respectively, each consist of an outer metal shell I4 havingan inner liner I5, of high heatresisting material such as .gypsumplaster or other insulatingv material commonly used in containers ofthis character. An inner metal shell i6 may also be employed to formY anenclosure for `the liner, as shown in Figure 3. The liner i5 mayfbeformed as usual in a single piece (eX- ceptng for the door) by moldingit within the outer shell I4 or by forming a separate hollow mold, andlater inserting it within the outer shell. [The insulating liner mayalso be formed of a plurality of separate slabs, or of other insulatingmaterial in more or less finely divided state.

The principal feature of my invention consists in disposing a relativelysmall amount of a heat expansible fire-resisting material within andadproved form of wall structure for containers of the characterdescribed wherein the suitable amount ofwexpansible insulating material,such asarrwriiculiteamis utilized as part` of the 'lui-ning mateialwithin "the" metal mc'fasi'ng." mfermwiculite has theSeeeialgllaraeteistiwheine ''xih sib'lrdgr abnormal neat so thatwn'rtljsing 1s subjected'tdre, th'yerm'iculite *becomes expanded*y andfills the hollow`spaces`otherwise fod within the metal casingof thecontainer.

The invention may best be understoo y' rereren'ce to the accompanyingdrawing in which:

Figure 1 is a sectional View of a fire-resisting container as it ismanufactured and used.

Figure 2 is a view similar to Figure 1, but showing the container afterit has been exposed to destructive re.

Figure 3 is an enlarged fragmentary section taken through one of thewalls of the container shown in Figure 1.

Figure 4 is a section similar to Figure 3, but showing the liner inexpanded condition after withstanding re.

Figures 5, 6 and '7 illustrate different methods which 'may be employedto apply the expanslble lining material to the Walls of the containerduring manufacture.

Referring now to details 0f the embodiment of jacent the outer metalshell Ill, in such position as to increase the effective thickness ofthe insulating liner, and to iill the voids which otherwise would beformed within the metal shell, when the container issubjected to adestructive fire, I find that vermiculite is especially suitable forthispurpose.

rerlni f uliterisamicacious mginggal, usually commonly used as aninsulating material after it has been subjected to expansion by heat. Itderives its name from its peculiar property of expanding under excessiveheat in such a manner that the expanded flakes resemble worms. Thisaction is explained by the fact that heat causes ,the manymicroscopically hin layers of each grain to expand into greatly enlargedcellular granules in the direction perpendicular to the layers.Ordinarily a batch of Vermiculite will expand to about fifteen times itsnatural volume when subjected to heat of about 350 F. or over. It isused commerciallyv in its eismd'statr many kinds of insulation yand asan aggregate for plaster and cement where special lightness is desired.

In my invention vermiculite is applied in its naturalunexpangdeglwstategvithin the outer metal shell I4`oth`'container I0,and preferably between said shell and the liner I5, as shown in Figure3. Various methods of application of the vermiculite may be employed.Figure 5 illusciably interfere 'v more finely divided state, it may bedisposed in close contact with the inner surface of the vermi- 1. In afire-resisting container, an outer metal casing having an associatedmolded hydrous 1ining of heat-resisting material, and a quantity ofvermiculite in its natural unexpanded state dis- Y posed in a relativelythin layer between said casgranules with a binder andLsjl'ellirectlyupon v thickness of natural granular state is mixed with any suitablelight binding material which will not apprewith the expansion of thevermiculite, and isa ie ith I5 is then applied withlite in any suitablemanner. For instance, if the can be poured .into direct contact `withthe layerl of vermiculite so as to become bonded thereto f during themolding process. Where the lining material I5is applied to th casing inthe form of individual slabs, or in culite layer, as indicated in Figure3.

An alternat lite as an adhesive layer to the entire inner surface of theouter shell I4 is shown in Figure 6' wherein the is mixedn nely dividedthe inn'er face of the'outer sli-l Another method of applying thevermiculite, illustrated in Figure '7, is particularly applicable whenthe main insulating liner I5 is applied to the structure in the form ofindividual slabs,

which are normally spaced slightly from the outer l thin layer ofvermiculite in its natural unexpandshell I4 so as to leave room for athin layer of vermiculite therebetween. In such case the vermiculite'maybe poured from a hopper I8 directly into the space between the metalshell I4 and the lining material I5. The vermiculite rntigrihegig pouredin itsnaturaldrnsiatencr agamcombingi' l a Suitable amgnmvbindsntahldntdmnlane if"desirfd Instead of applying the layer of ver. ,1

miculite to the interior surface of the outer wall or pouring it betweenthe outer wall and the liner 40v as previously described, thevermiculite may also.

if desired, be applied to the exterior surface of the L insulatinglining I5 before the latter is inserted...v .Within the casing.

be understood the vermiculite is It will now applied between the outershell I4 and the lining material I5 in position to become expanded underre conditions and thus increase the effective thickness of theinsulation as .the outer walls bulge f outwardly due to the pressure ofgases generated 5U between the outer shell I4 and the liner I5. It willbe further understood that vermiculite can also be applied to the innermetal shell I6 if desired,

' :but it will not be so eicient, and may not even be necessary, ifsufficient protection against heat aioi'ded by the liner I5 and theconduction is trowel or the like 5- to form a thin layer I9 of, say,one-quarter inch f Y in thickness to the inner surface of the outerVshell I4. The main liner in the outer shell next to said layer ofvermicu- :1

. lining material is molded within the outer shell itl V"understood aslimiting myself to the specic form -andarrangement of materials hereindescribed and' shown, but that various modiiications thereof *may beemployed without departing from the spirit and scope of my invention asdened in the method of applying the vermicuall layer I9 of vermiculiteon the outer face of the latter.

It will also be understood that limited amounts of unexpandedvermiculite can also be employed to .special advantage along the jointsseparating vindividual slabs of lining material, so as .toinsure tightlypacked joints between adjoining slabs due to the expansion of thevermiculite under re conditions Although I have shown and describedcertain i embodiments of my invention, I do not wish to be appendedclaims.

,What is claimed is:

ing and its lining so as to increase the effective 2. In anre-.resisting container, an out-er metal easing having an associatedmolded hydrous lining of heat-resisting material, and a relatively edstate fixed in a binder applied to the exterior 'surface of said liningso as to increase the effective thickness of the insulation within saidcasing when said vermiculite becomes expanded under abnormal heat.

. 3. In a nre-resisting container, an outer metal casing having anassociated molded hydrous 1ining of heat-resisting material and arelatively thin layer of vermiculite in its natural unexpandyed statefixed in a binder applied adhesively to the l inner surface of saidcasing in position to expand rv.within the voids produced between saidcasing 'and its lining when said container is subjected to abnormalheat.

the insulation within said casing when said vermiculite becomes expandedunder. l vabnormal heat.

' 4. In a nre-resisting container, an outer metal i casing having anassociated molded hydrous linf. ing of heat-resisting material and aquantity of jected to abnormal heat.

. JOHN H. PAGE.

